Boro managed to cap off a productive summer on deadline day as striker Andraz Sporar and midfielder James Lea Siliki joined the Teessiders from Sporting Lisbon and Stade Rennais respectively.
They followed Joe Lumley, Sammy Ameobi, Uche Ikpeazu, Martin Payero, Matt Crooks, Sol Bamba, Lee Peltier, Luke Daniels, Toyosi Olusanya and Onel Hernandez to the Riverside.
In the aforementioned signings there is a real mix of players with Championship experience and arrivals from abroad.
At this stage it’s hard to judge how the players from overseas will fare this season, making it difficult to predict Boro's strongest side.
Of course fans will have different opinions and the team will change throughout the campaign as injuries occur and the team changes system.
Following the end of the window, here’s how Boro’s squad is shaping up.
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1. GK: Joe Lumley
Ha been Boro's first-choise option between the sticks since his arrival from QPR this summer. Photo: George Wood
2. RB: Anfernee Dijksteel
Can operate on the right of a back four or in a back three and will be able to change positions when Boro alter their formation. Photo: George Wood
3. CB: Grant Hall
Has established himself as a regular starter after some impressive performances in the second half of last season. Photo: George Wood
4. CB: Dael Fry
Back from an injury he suffered at the end of last season. Has been labelled the best centre-half in the Championship by Warnock. Photo: George Wood